Salt Lake Valley motorists can once again add "pick an alternate route" to their list of things to do.

The Utah Department of Transportation and its I-15 reconstruction contractor have released a list of 10 ramp closures and 13 ramp openings scheduled during the next five months.Three of the closures will occur in late August. Eight openings are set for September. All of the changes will take place in the middle and southern half of the 17-mile project corridor.

The exact shutdown date is known for only two of the ramps: The northbound I-15 off- and onramps at 10600 South will close Aug. 24 and reopen about three months later. The southbound I-15 ramps at 10600 South, now closed, are scheduled to reopen in October.

Specific dates for the other closures and openings will be released as they are established, officials said.

Also, northbound I-15 between the I-215 south junction and 7200 South will be reduced from three lanes of traffic to two in September. That restriction will continue until November, a spokesman for Wasatch Constructors said Thursday. A similar reduction of traffic lanes on southbound I-15 in that area is not currently planned.

Here are the ramp changes announced this week, listed by month. For closures, tentative re-opening dates are shown in parentheses.

August

- Closures - Aug. 24, northbound I-15 offramp and onramp at 10600 South (November '98); Eastbound I-215 connection to northbound I-15 (autumn '00).

- Openings - none.

September

- Closures - Southbound I-15 offramp and onramp at 5300 South (autumn '99); northbound I-15 offramp at 7200 South (December '98).

- Openings - Southbound I-15 offramp and onramp at 4500 South; southbound I-15 offramp and onramp at 7200 South; eastbound I-215 offramp to 7200 South; 7200 South onramp to eastbound I-215; eastbound I-215 connection to southbound I-15; northbound I-15 connection to eastbound I-215.

October

- Closures - Southbound I-15 offramp and onramp at 9000 South (autumn '99).

- Openings - Southbound I-15 offramp and onramp at 10600 South.

November

- Closures - Northbound I-15 offramp and onramp at 9000 South (autumn '99).

- Openings - Northbound I-15 offramp and onramp at 10600 South.

December

- Closures - none.

- Openings - Northbound I-15 offramp at 7200 South.

In addition to the ramps, Vine Street will open for one lane of traffic in each direction in September. Also that month, 7200 South under I-15 will completely re-open.

UDOT recommends that businesses and motorists affected by the closures begin choosing alternate routes now to avoid delays when they occur.

Some closings and openings could be pushed back due to weather conditions or other factors. For the latest schedule updates, check Wasatch Construc-tor's Web site at (www.I-15.com).

In the next few weeks, Wasatch plans to release a schedule for ramp openings and closures in downtown Salt Lake City and dates when freeway traffic will be switched onto new segments of the interstate.

Completion of the project is about three years away.